Fix EZP-27252: Wrong message when deleting trash content

[adamwojs]

JIRA issue: https://jira.ez.no/browse/EZP-27252

Description

This PR fixes missing % for count parameter in source/target translation of items.permanently.deleted key in /Resources/translations/trash.en.xlf

Steps to reproduce:

• On the admin interface, go to trash and click on "Empty the trash";
• After trash is deleted, the following message is displayed at the bottom:
  %count items were permanently deleted.
  ...which does not reflect the number of contents deleted - see attached screenshot.

[yannickroger]

You need to fix it in 1.7 (oldest supported branch), it is also happening there: https://github.com/ezsystems/PlatformUIBundle/blob/1.7/Resources/translations/trash.en.xlf#L52

[yannickroger]

Thanks @adamwojs

[adamwojs]

You welcome @yannickroger!